Bear in mind that the other military use of the Spey was on the Nimrod. The sortie profiles were unique, involving high and low level and routine in flight shutdown and relight. On the maritime aircraft at least one engine would be shut down on the majority of sorties. Relighting was usually accomplished by windmill starting for routine relights or air assist cross bleed when relighting following engine failure in 2+2 configuration. It was a reliable power plant, I never had one fail in flight or fail or to relight in 13 years on the aircraft.
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